Safety device for dies



H. J. GUZEWICZ SAFETY DEVICE FOR DIES April4, 1950 Filed June 5, 1946 IN VEN TOR.

Patented Apr. 4, 1950 UNITED STATES PATENT OFFICE SAFETY DEVICE FOR DIES Application June 3, 1946, Serial No. 674,122

5 Claims.

This invention relates to improvements in stamping or forming dies.

It is customary to provide the opposed members of dies with co-actin guide elements which function to guide the said members together into properly mated position and to maintain them in said position during the stamping operation. conventionally the guide means takes the form of a sleeve on one of the die members and a pin on the other member aligned with the sleeve and formed to neatly fit within the latter. In some cases the sleeve and pin are in constant engagement during the entire stroke of the press in which the die may be installed; but in many cases, because of inadequate space, or for other reasons, the pin enters the sleeve only after the die members have advanced close to the shut position of the die or immediately in advance of the point where the work occurs.

In these latter cases, where the guide elements are separated during a portion of the movement of the die members between the shut and open positions, there is a substantial hazard to the operator of the press arising from ossible inadvertent insertion of the hand or arm between the separated guide elements as the latter are moving together, and a principal object of the present invention is to provide means for effectively eliminating this: hazard.

More specifically, an object of the invention is to provide, in dies of the type comprisin guide elements attached respectively to the opposed relatively movable members of the die so as to be interengaged when the die is shut and disengaged when the die is fully opened, a safety device in the form of a guard element operatively associated with said guide elements and constructed and arranged to bridge the space therebetween when the said elements are separated.

The invention also resides in certain structural arrangements and devices employed in adapting the principle of the aforesaid safety device to the requirements of different dies and presses as hereinafter described and as illustrated in the attached drawings wherein:

Fig. 1 is a fragmentary semi-diagrammatic sectional view illustrating a device made in accordance with the invention;

Fig. 2 is a fragmentary sectional view illustrating a modification within the scope of the invention, and

Fig. 3 is a diagrammatic sectional view illustrating still another modification.

With reference to Fig. 1 of the drawings, the numeral l designates a portion of the lower die of a set, and z a portion of the companion upper die. The fixed platen of a press, upon which the lower die member I is mounted, is indicated at 3, and the relatively movable platen of the press, to which the upper die member 2 is secured, is indicated at t.

In accordance with the conventional practice a pin 5 is mounted in the lower die member 1, said pin extending vertically upward, and the upper die member 2 carries a sleeve 6 which is in axial alignment with the pin 5 so that when the upper die member 2 moves downwardly the sleeve 5 will eventually pass on to the upper end of the pin 5. The pin is formed to neatly fit the sleeve and when the element are engaged as described, they serve to establish a fixed normal positional relationship between the two die members which is maintained during the remainder of the workin stroke and during actual performance of said work. When the upper die is retracted to the open position as shown in Fig. 1, the guide element 6 is elevated above the upper end of the which the hand of the operator might inadvertently be inserted during the working stroke of the press.

In accordance with the present invention I provide a guard element 1 which is slidably en'- gaged with the guide element 5 and which moves with the guide element 6, this guard element being constructed and arranged so that it bridges the space between the guide elements in all relative positions of the die members wherein the said guide elements are separated. The design shown in Fig. 1, for example, may be used in all dies where the separation of the guide elements 5 and 6 does not exceed the effective length of the element 1, i. e., of that portion of the element 1 which extends beyond the lower end of the guide 6. In the present instance the element 5 is provided with a longitudinal bore 8 within which the guard pin 1 slides and the upper end of the pin 1 is provided with a flange 9 having in the present instance a beveled peripheral edge Ill which seats upon the inner end of the sleeve 6 and is confined by the adjoining surface of the upper platen 4 of the press. A clearance is provided between the upper surface of the flange 9 and the adjoining surface of the platen 4 so as to provide for limited free movement of the pin 7 with respect to the upper die member as a safety factor against the possible meeting of the lower end of the pin 1 with the bottom of the bore of the pin 5. The upper end of the pin 5 is also provided with rounded edges as indicated at H to avoid sharp corner or quare shoulders at this point. In operation if an operator places his hand upon the upper end of the pin 5 when the said die members I and 2 are separated, the downward movement of the upper die 2 will cause the lower rounded edge l2 of the sleeve 6 to displace the fingers downwardly over the rounded terminal surface H of the pin 5 and will avoid the severe crushing of the hand of the operator which might occur were the guard pin 1 not employed.

In those cases where the stroke of the press exceeds the shut height of the die, a telescopic guard pin of the type illustrated in Fig. 2 may be employed. It will be apparent that this telescopic arrangement will permit a considerably wider separation of the die members without separation of the guard from the guide pin with which it is slidably associated.

Where the shut height of the die materially exceeds the height of the guide pin and Where the space permits, an arrangement such as illustrated in Fig. 8 may be employed to advantage. In this case the lower die member is designated by the reference numeral l3 and the upper die member by the numeral I 4. A guide pin I5 is mounted in the lower die member l3 and cooperates with a sleeve 16 on the upper member M to guide the dies accurately into the operatin or shut position. The guide pin i5 is made hollow, as in the embodiment of Fig. 1, but in this case the lower die member [3 is provided with an aperture i! which forms a continuation of the bore of the pin IS. A guard pin is slidably engaged in the bore of the guide pin l5 and this guard pin i8 is of relatively great length so as to occupy the position shown in Fig. 3 when the dies are closed. In this position the lower end of the guard pin extends downwardly through the aperture l1 and seats upon the upper surface of the lower press platen IS. The upper end of the guard pin 18 extends into the space 20 in the upper die member 14. When the press platen 2| is elevated, carrying with it the upper die memher M, the inner end of the sleeve l 5 will eventually engage a flange 22 at the upper end of the guard pin I8 and will then in the continued upward movement of the die member elevate the guard pin. This pin, however, is of such length that in the extreme open position of the die the lower end of the guard pin will remain in the bore of the guide pin I 5. The principle and mode of operation of this embodiment of the invention will be apparent from the foregoing description.

The device may be readily adapted to existing guide devices at a minimum expense for materials and installation, and the invention accordingly provides a simple, inexpensive, and highly efiective safety device. It is to be noted that the guard pin has no direct part in the actual die-guiding function which is done entirely by the guide pin and coactive sleeve.

I claim:

1. In a die set of the type comprisin telescopin guide elements attached respectively to the opposed relatively movable members of the die so as to be interengaged when the die is shut and disengaged when the die is fully open, guard means in the interior of said guide elements constructed and arranged to bridge the intervening space between the said elements when the latter are disengaged.

2. A guard means in accordance with claim 1 comprising a guard element movable with one of said guide elements and slidably interengaged with the other of said guide elements.

3. In a die set of the type having guide means including a sleeve element attached to one of the relatively movable die members and a pin element attached to the other of said members in axial alignment with the sleeve so as to enter the latter when the die is shut, said pin and sleeve being disengaged when the die is open, and a guard element mounted within one of said guide elements and telescopically engaged with and inside of the other of said guide elements.

4. In a press, a fixed platen and a movable platen adapted to reciprocate to and from the fixed platen, a die set comprising separable members attached respectively to said platens, a sleeve on one of said members, a hollow pin on the other of said members aligned with the sleeve and adapted to enter the sleeve when the die members move together to shut the die, said sleeve and pin constituting a guide for said die members and being disengaged when the said members are separated to open the die, and a guard element slidably telescoped in said pin and movable with said sleeve so as to continuously bridge the space between the sleeve and pm when the latter are disengaged.

5. In a die set of the type comprising guide elements attached respectively to the opposed relatively movable members of the die so as to be interengaged when the die is shut and disengaged when the die is fully open, said die elements consisting respectively of a sleeve and a pin formed to -fit said sleeve and having a longitudinal bore. and guard means operatively associated with said guide elements and constructed and arranged to bridge the intervening space between the said elements when the latter are disengaged, said guard means including a pin mounted on and extending axially through said sleeve and telescopically engaged within the bore of said guide pin.

HENRY J. GUZEWICZ.

REFERENGES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name I Date 2,141,027 Wie sman Dec. 20, 1938 2,320,240 Janiszewslzi May 25, 1943 

